MEAN MAGNETIC FIELD GENERATION IN IDEAL FLUID
Session: Magnetohydrodynamics 3
Session starts: Thursday 27 August, 15:00
Presentation starts: 15:00
Room: Room I
Krzysztof Mizerski (Institute of Geophysics, Polish Academy of Sciences, Warsaw, Poland)
The so-called alpha-effect for large scale fields occurring in turbulent MHD flows is a typically invoked mechanism for mean field generation in all astrophysical objects such as stars, planets, accretions disks, galaxies etc. Although the resistivity of the fluid tends to damp the magnetic fields growth it is helpful in generation of the large scale electromotive force. However, high resolution simulations of Tobias & Cattaneo Nature, 497, 463-465, 2013 show that the resistivity is not a necessary factor for large scale field generation. Here it is demonstrated that there exists a mechanism for mean electromotive force generation based on interactions of turbulent small scale fields, which does not require the resistivity to operate and which is potentially very effective.